Terminal, device, base station, system and methods for speed estimation techniques

ABSTRACT

A first terminal device for use with a wireless telecommunications system, the first terminal device comprising: a transceiver operable to exchange signalling with a second terminal device using communication resources from within one of a plurality of sets of communication resources, each set of communication resources being associated with a different respective range of possible speeds of the first terminal device, the association being determined in accordance with a predetermined characteristic of the sets of communication resources; and a controller operable to control the transceiver to exchange signalling with the second terminal device using communication resources from within the set of communication resources associated with the range of possible speeds of the first terminal device within which a determined speed of the first terminal device is found.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. application Ser. No.15/769,935, filed Apr. 20, 2018, which is based on PCT filingPCT/EP2016/076523, filed Nov. 3, 2016, which claims priority to EP15193158.1, filed Nov. 5, 2015, the entire contents of each areincorporated herein by reference.

BACKGROUND Field of the Disclosure

The present disclosure relates to a terminal device, base station,system and methods.

Description of the Related Art

The “background” description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent it is described in thebackground section, as well as aspects of the description which may nototherwise qualify as prior art at the time of filing, are neitherexpressly or impliedly admitted as prior art against the presentinvention.

The automotive industry has been working for several years on solutionsto enable communication with and between vehicles so as to help improvetraffic flow and safety. These techniques range from automatic tollingtechnologies to collision prevention mechanisms, and are generally knownas Intelligent Transport Systems (ITS). Currently, the main radiotechnology that is being considered in standards projects is a WLANderivative 802.11p, which would be used for broadcasting ITS informationto vehicles. This constitutes a so-called Dedicated Short RangeCommunication (DSRC) system that is deployed at 5.9 GHz ITS band inEurope (there may be different ITS bands in use in other regions, e.g.700 MHz in Japan).

The effective range of DSRC systems is a few hundred meters and theservices are broadcast oriented (emergency vehicle notices, forexample). It is considered that mobile telecommunications networks, suchas Long Term Evolution (LTE) on International Mobile Telecommunications(IMT) bands, could fulfil at least some of the ITS needs, and alsoprovide wider and cheaper coverage. In particular, where the existingcellular network already covers roadways the capital expenditure costsmay be a fraction of what is needed for setting up a new DSRC-based ITSnetwork.

LTE is understood to play an increasingly important role in theconnected vehicle ecosystem. LTE based solutions may in particular bringimprovements in spectral efficiency, effective communications range,throughput, error resiliency and Quality of Service. It is noted thatLTE networks are finding new areas of deployment with each new 3GPPRelease. Release 12 introduced Public Safety aspects on device-to-device(D2D) communications, and Release 13 continues to develop the D2Dconcepts further. In Release 14 stage 3GPP starts to discuss vehicularcommunications, effectively considering whether and how LTE networkscould support Intelligent Transport Systems (ITS).

Connected vehicle systems are called V2X, which consists of V2V(vehicle-to-vehicle), V2P (vehicle-to-pedestrian) and V2I(vehicle-to-infrastructure). Infrastructure in this case may be theroadside ITS related infrastructure or backbone systems in Internet ormobile networks. Some examples or services in connected car environmentare Cooperative Awareness Message (CAM) and Decentralised EnvironmentalNotification (DEN). These constitute applications such as allowingemergency vehicles to broadcast their presence and allowing roadsideinfrastructure to broadcast speed limit information to vehicles. It isenvisaged that LTE will work with 802.11p in order to provide suchservices, and that both radio technologies will likely find applicationsin the connected vehicle ecosystem.

A Study Item (SI) has been agreed in 3GPP on V2X communication (Vehiclecommunication) to study possible enhancement to LTE to support V2Xcommunication. The study item is RP-151109 “New SI proposal: FeasibilityStudy on LTE-based V2X Services” from LG Electronics, CATT, Vodafone andHuawei (3GPP TSG RAN Meeting #68 Malmo, Sweden, Jun. 15-18, 2015) [1].

It has been proposed that V2X communications may be implemented usingnetwork nodes (such as dedicated Road Side Units (RSUs) and/or cellularbase stations such as enhanced Node Bs (eNBs)) which communicate withthe user equipment (UE) of vehicles and which assign certainconfigurations to the vehicle UEs. Such configurations includecommunication resources (in particular, radio resources) for use by thevehicle UEs in V2X communications. In particular, such network nodes mayallocate D2D radio resources for use in V2X communications.

It is known that the speed of a UE has implications on various aspectsof its operation, for example mobility and measurements and thereliability of communication. Due to the wide range of speeds consideredfor vehicular communication it is likely that the speed of the vehicleneeds to be taken into account when providing configuration(s) to thedevices. For example, mobility related measurement events provideparameters which are scaled according to the UE state. Thetime-to-trigger for measurement events can be extended at higher speedsto avoid frequent handovers (and risk of handover failures) forexample—this is a particular problem when there are small cells deployed(which is likely to be the case with RSUs because their small cell sizeadds to the problem, particularly at high speeds).

In addition, it is also known that the conventional speed estimationtechniques in 3GPP systems are unreliable. This provides an extrachallenge when trying to design a reliable and efficient system forvehicular communications. The conventional speed estimation counts thenumber of cell changes, and based on this count the UE (or network NW)determines the mobility state to be low, medium or high. It has beenacknowledged during earlier studies on heterogeneous network that suchspeed estimation techniques can be unreliable.

SUMMARY

In a first aspect, the present technique provides a first terminaldevice for use with a wireless telecommunications system, the firstterminal device comprising: a transceiver operable to exchangesignalling with a second terminal device using communication resourcesfrom within one of a plurality of sets of communication resources, eachset of communication resources being associated with a differentrespective range of possible speeds of the first terminal device, theassociation being determined in accordance with a predeterminedcharacteristic of the sets of communication resources; and a controlleroperable to control the transceiver to exchange signalling with thesecond terminal device using communication resources from within the setof communication resources associated with the range of possible speedsof the first terminal device within which a determined speed of thefirst terminal device is found.

In an embodiment, the transceiver is operable to receive signalling frominfrastructure equipment identifying communication resources for use bythe first terminal device in exchanging signalling with the secondterminal device, the communication resources identified by thesignalling received from the infrastructure equipment being selected bythe infrastructure equipment from one or more of the sets ofcommunication resources.

In an embodiment, the signalling received from the infrastructureequipment identifies the communication resources of each of the sets ofcommunication resources, and the controller is operable to: determinethe speed of the first terminal device; select the set of communicationresources associated with the range of possible speeds of the firstterminal device within which the determined speed of the first terminaldevice is found; and control the transceiver to exchange signalling withthe second terminal device using communication resources from theselected set.

In an embodiment, the controller is operable to: determine the speed ofthe first terminal device; control the transceiver to transmitsignalling to the infrastructure equipment identifying the determinedspeed; receive the signalling from the infrastructure equipmentidentifying communication resources for use by the first terminal devicein exchanging signalling with the second terminal device, the identifiedcommunication resources being communication resources from the set ofcommunication resources associated with the range of possible speeds ofthe first terminal device within which the determined speed of the firstterminal device is found; and control the transceiver to exchangesignalling with the second terminal device using a portion of theidentified communication resources.

In an embodiment, the signalling received from the infrastructureequipment identifies the communication resources of each of a portion ofthe sets of communication resources, each set in the portion of setsbeing associated with a different respective range of possible speeds ofthe first terminal device within a predetermined speed constraint, andthe controller is operable to: determine the speed of the first terminaldevice; determine whether the speed of the first terminal device iswithin the predetermined speed constraint; if it is determined that thespeed of the first terminal device is within the predetermined speedconstraint, select the set of communication resources identified in thesignalling received from the infrastructure equipment which isassociated with the range of possible speeds of the first terminaldevice within which the determined speed of the first terminal device isfound, and control the transceiver to exchange signalling with thesecond terminal device using communication resources from the selectedset; and if it is determined that the speed of the first terminal deviceis outside of the predetermined speed constraint, control thetransceiver to transmit signalling to the infrastructure equipmentidentifying the speed of the first terminal device, control thetransceiver to receive new signalling from the infrastructure equipmentnewly identifying communication resources for use by the first terminaldevice in exchanging signalling with the second terminal device, thenewly identified communication resources being communication resourcesfrom the set of communication resources associated with the range ofpossible speeds of the first terminal device within which the determinedspeed of the first terminal device is found, and control the transceiverto exchange signalling with the second terminal device using a portionof the newly identified communication resources.

In an embodiment, the predetermined speed constraint is that eachpossible speed of the first terminal device within the range of possiblespeeds associated with each set of communication resources in theportion of sets of communication resources is less than a predeterminedspeed.

In an embodiment, the predetermined speed constraint is that eachpossible speed of the first terminal device within the range of possiblespeeds associated with each set of communication resources in theportion of sets of communication resources is greater than apredetermined speed.

In an embodiment, the predetermined characteristic in accordance withwhich each set of communication resources is associated with a differentrespective range of possible speeds of the first terminal device is acell coverage area over which each set of communication resources isutilised, wherein a set of communication resources utilised over alarger coverage area is associated with a higher range of possiblespeeds of the first terminal device and a set of communication resourcesutilised over a smaller coverage area is associated with a lower rangeof possible speeds of the first terminal device.

In an embodiment, the controller is operable to receive an input fromexternal equipment in order to determine the speed of the first terminaldevice.

In an embodiment, the transceiver is operable to exchange signallingwith the second terminal device using communication resources fromwithin one or more further sets of communication resources, each furtherset of communication resources being associated with a different eventpriority level detectable by the first terminal device, the eventpriority level indicating a level of severity of an event detectable bythe first terminal device; and the controller is operable to: determinewhether an event has occurred; and when it is determined that an eventhas occurred, determine the event priority level of the event, andcontrol the transceiver to exchange signalling with the second terminaldevice using communication resources from within the further set ofcommunication resources associated with the determined event prioritylevel.

In a second aspect, the present technique provides Infrastructureequipment for use with a wireless telecommunications system, theinfrastructure equipment comprising: a transceiver; and a controller;wherein the controller is operable to control the transceiver totransmit signalling to a first terminal device identifying communicationresources for use by the first terminal device in exchanging signallingwith a second terminal device, wherein the communication resourcesidentified by the signalling transmitted by the transceiver are selectedby the controller from within one or more of a plurality of sets ofcommunication resources, each set of communication resources beingassociated with a different respective range of possible speeds of thefirst terminal device as determined in accordance with a predeterminedcharacteristic of the sets of communication resources, and wherein thecommunication resources of a particular set of communication resourcesare for use by the first terminal device in exchanging signalling withthe second terminal device when the first terminal device is travellingat a speed which is within the range of possible speeds associated withthat particular set of communication resources.

In an embodiment, the signalling transmitted to the first terminaldevice identifies the communication resources of each of the sets ofcommunication resources.

In an embodiment, the transceiver is operable to receive signalling fromthe first terminal device indicative of the speed of the first terminaldevice; the controller is operable to determine communication resourcesfor use by the first terminal device in exchanging signalling with thesecond terminal device, the identified communication resources beingcommunication resources from the set of communication resourcesassociated with the range of possible speeds of the first terminaldevice within which the indicated speed of the first terminal device isfound; and the transceiver is operable to transmit signalling to thefirst terminal device indicative of the determined communicationresources.

In an embodiment, the signalling transmitted to the first terminaldevices identifies the communication resources of each of a portion ofthe sets of communication resources, each set in the portion of setsbeing associated with a different respective range of possible speeds ofthe first terminal device within a predetermined speed constraint, andwherein: the transceiver is operable to receive signalling from thefirst terminal device indicative of the speed of the first terminaldevice when the speed of the first terminal device is outside of thepredetermined speed constraint; in response to receiving the signallingfrom the first terminal device indicative of the speed of the firstterminal device, the controller is operable to newly determinecommunication resources for use by the first terminal device inexchanging signalling with the second terminal device, the newlydetermined communication resources being communication resources fromthe set of communication resources associated with the range of possiblespeeds of the first terminal device within which the determined speed ofthe first terminal device is found; and the transceiver is operable totransmit signalling to the first terminal device indicative of the newlydetermined communication resources.

In an embodiment, the predetermined speed constraint is that eachpossible speed of the first terminal device within the range of possiblespeeds associated with each set of communication resources in theportion of sets of communication resources is less than a predeterminedspeed.

In an embodiment, the predetermined speed constraint is that eachpossible speed of the first terminal device within the range of possiblespeeds associated with each set of communication resources in theportion of sets of communication resources is greater than apredetermined speed.

In an embodiment, the predetermined characteristic in accordance withwhich each set of communication resources is associated with a differentrespective range of possible speeds of the first terminal device is acell coverage area over which each set of communication resources isutilised, wherein a set of communication resources utilised over alarger coverage area is associated with a higher range of possiblespeeds of the first terminal device and a set of communication resourcesutilised over a smaller coverage area is associated with a lower rangeof possible speeds of the first terminal device.

In an embodiment, the controller is operable to control the transceiverto transmit signalling to the first terminal device identifying furthercommunication resources for use by the first terminal device inexchanging signalling with the second terminal device, wherein thefurther communication resources identified by the signalling transmittedby the transceiver are selected by the controller from within one ormore further sets of communication resources, each further set ofcommunication resources being associated with a different event prioritylevel detectable by the first terminal device, the event priority levelindicating a level of severity of an event detectable by the firstterminal device, and wherein the communication resources of a particularfurther set of communication resources are for use by the first terminaldevice in exchanging signalling with the second terminal device when thefirst terminal device determines that an event has occurred and that theevent priority level of the determined event is the event priority levelassociated with that particular further set of communication resources.

In a third aspect, the present technique provides a wirelesstelecommunications system comprising a first terminal device accordingto the first aspect, a second terminal device with which the firstterminal device is operable to exchange signalling, and infrastructureequipment according to the second aspect.

In a fourth aspect, the present technique provides a method of operatinga first terminal device for use with a wireless telecommunicationssystem, the method comprising: controlling a transceiver of the firstterminal device to exchange signalling with a second terminal deviceusing communication resources from within one of a plurality of sets ofcommunication resources, each set of communication resources beingassociated with a different respective range of possible speeds of thefirst terminal device, the association being determined in accordancewith a predetermined characteristic of the sets of communicationresources; and controlling the transceiver to exchange signalling withthe second terminal device using communication resources from within theset of communication resources associated with the range of possiblespeeds of the first terminal device within which a determined speed ofthe first terminal device is found.

In a fifth aspect, the present technique provides a method of operatinginfrastructure equipment for use with a wireless telecommunicationssystem, the method comprising controlling a transceiver of theinfrastructure equipment to transmit signalling to a first terminaldevice identifying communication resources for use by the first terminaldevice in exchanging signalling with a second terminal device, whereinthe communication resources identified by the signalling transmitted bythe transceiver are selected from within one or more of a plurality ofsets of communication resources, each set of communication resourcesbeing associated with a different respective range of possible speeds ofthe first terminal device as determined in accordance with apredetermined characteristic of the sets of communication resources, andwherein the communication resources of a particular set of communicationresources are for use by the first terminal device in exchangingsignalling with the second terminal device when the first terminaldevice is travelling at a speed which is within the range of possiblespeeds associated with that particular set of communication resources.

In a sixth aspect, the present technique provides a first terminaldevice for use with a wireless telecommunications system, the firstterminal device comprising: transceiver circuitry operable to exchangesignalling with a second terminal device using communication resourcesfrom within one of a plurality of sets of communication resources, eachset of communication resources being associated with a differentrespective range of possible speeds of the first terminal device, theassociation being determined in accordance with a predeterminedcharacteristic of the sets of communication resources; and controllercircuitry operable to control the transceiver to exchange signallingwith the second terminal device using communication resources fromwithin the set of communication resources associated with the range ofpossible speeds of the first terminal device within which a determinedspeed of the first terminal device is found.

In a seventh aspect, the present technique provides infrastructureequipment for use with a wireless telecommunications system, theinfrastructure equipment comprising: transceiver circuitry; andcontroller circuitry; wherein the controller circuitry is operable tocontrol the transceiver circuitry to transmit signalling to a firstterminal device identifying communication resources for use by the firstterminal device in exchanging signalling with a second terminal device,wherein the communication resources identified by the signallingtransmitted by the transceiver circuitry are selected by the controllercircuitry from within one or more of a plurality of sets ofcommunication resources, each set of communication resources beingassociated with a different respective range of possible speeds of thefirst terminal device as determined in accordance with a predeterminedcharacteristic of the sets of communication resources, and wherein thecommunication resources of a particular set of communication resourcesare for use by the first terminal device in exchanging signalling withthe second terminal device when the first terminal device is travellingat a speed which is within the range of possible speeds associated withthat particular set of communication resources.

The foregoing paragraphs have been provided by way of generalintroduction, and are not intended to limit the scope of the followingclaims. The described embodiments, together with further advantages,will be best understood by reference to the following detaileddescription taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the disclosure and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1 schematically illustrates some basic functionality of aconventional mobile telecommunications network;

FIG. 2 schematically illustrates an example heterogeneous system forcommunicating with at least one terminal device;

FIG. 3 schematically illustrates a base station according to anembodiment of the present disclosure;

FIG. 4 schematically illustrates a terminal device according to anembodiment of the present disclosure;

FIG. 5 schematically shows a first signalling arrangement according toan embodiment of the present disclosure;

FIG. 6 schematically shows a second signalling arrangement according toan embodiment of the present disclosure; and

FIG. 7 schematically shows a third signalling arrangement according toan embodiment of the present disclosure.

DESCRIPTION OF THE EMBODIMENTS

Referring now to the drawings, wherein like reference numerals designateidentical or corresponding parts throughout the several views.

FIG. 1 provides a schematic diagram illustrating some basicfunctionality of a conventional mobile telecommunications network, usingfor example a 3GPP defined UMTS and/or Long Term Evolution (LTE)architecture. The mobile telecommunications network/system 100 of FIG. 1operates in accordance with LTE principles and which may be adapted toimplement embodiments of the disclosure as described further below.Various elements of FIG. 1 and their respective modes of operation arewell-known and defined in the relevant standards administered by the3GPP® body, and also described in many books on the subject, forexample, Holma H. and Toskala A [2]. It will be appreciated thatoperational aspects of the telecommunications network which are notspecifically described below may be implemented in accordance with anyknown techniques, for example according to the relevant standards.

The network 100 includes a plurality of base stations 101 connected to acore network 102. Each base station provides a coverage area 103 (i.e. acell) within which data can be communicated to and from terminal devices104. Data is transmitted from base stations 101 to terminal devices 104within their respective coverage areas 103 via a radio downlink. Data istransmitted from terminal devices 104 to the base stations 101 via aradio uplink. The uplink and downlink communications are made usingradio resources that are licensed for use by the operator of the network100. The core network 102 routes data to and from the terminal devices104 via the respective base stations 101 and provides functions such asauthentication, mobility management, charging and so on. Terminaldevices may also be referred to as mobile stations, user equipment (UE),user terminal, mobile terminal, mobile device, terminal, mobile radio,and so forth. Base stations may also be referred to as transceiverstations/nodeBs/e-nodeBs/eNodeB, eNB, and so forth. Base stations andRSUs may generally be referred to as infrastructure equipment.

Mobile telecommunications systems such as those arranged in accordancewith the 3GPP defined Long Term Evolution (LTE) architecture use anorthogonal frequency division multiplex (OFDM) based interface for theradio downlink (so-called OFDMA) and the radio uplink (so-calledSC-FDMA).

The base stations 101 of FIG. 1 may be realised as any type of evolvedNode B (eNodeB) such as a macro eNodeB and a small eNodeB. The smalleNodeB may be an eNodeB such as a pico eNodeB, a micro eNodeB, and ahome (femto) eNodeB that covers a cell smaller than a macro cell.Instead, the base station 101 may be realized as any other types of basestations such as a NodeB and a base transceiver station (BTS). The basestation 101 may include a main body (that is also referred to as a basestation apparatus) configured to control radio communication, and one ormore remote radio heads (RRH) disposed in a different place from themain body. In addition, various types of terminals, which will bedescribed below, may each operate as the base station 101 by temporarilyor semi-persistently executing a base station function.

Any of the terminal devices 104 may be realized as a mobile terminalsuch as a smartphone, a tablet personal computer (PC), a notebook PC, aportable game terminal, a portable/dongle type mobile router, and adigital camera, or an in-vehicle terminal such as a car navigationapparatus. The terminal device 104 may also be realized as a terminal(that is also referred to as a machine type communication (MTC)terminal) that performs machine-to-machine (M2M) communication.Furthermore, the terminal device 104 may be a radio communication module(such as an integrated circuit module including a single die) mounted oneach of the terminals.

In the present disclosure, a base station providing a small cell isgenerally differentiated from a conventional base station mostly (andsometimes exclusively) in the range provided by the base station. Smallcells include for example the cells also called femtocell, picocell ormicrocell. In other words, small cells can be considered as similar tomacrocells in the channels and features provided to the terminals, butwith the use of less power for base station transmissions, which resultsin a smaller range. A small can therefore be the cell or coverageprovided by a small cell base station. In other examples, the term smallcell can also refer to a component carrier when more than one componentcarriers are available.

Moreover, mobile networks can also include Relay Nodes (RN) which canfurther increase the complexity of the mobile system and of thereduction of interference in a small cell network. Relay technologiesare known generally to provide an arrangement for receiving signals froma base station and for retransmitting the received signals to a UE in amobile communications network, or to receive signals transmitted from aUE for re-transmission to a base station of a mobile communicationsnetwork. The aim of such relay nodes is to try to extend a radiocoverage area provided by a mobile communications network to reachcommunications devices which would otherwise be out of range of themobile communications network or to improve the ratio of successfultransmissions between a terminal and a base station.

A mobile network which includes a variety of base stations and/or relaynodes (e.g. macro-cell base stations, small cell base stations and/orrelays) is sometimes referred to as a heterogeneous network.

FIG. 2 illustrates an example heterogeneous system 200 for communicatingwith at least a terminal 231. In this system 200, a base station 201provides a macrocell and six base stations 211-216 provide small cellcoverage, potentially overlapping with the coverage of the base station201. Additionally, three RN 221-223 are provided and are operating withbase stations 201, 214 and 212, respectively. A relay node can generallybe defined as a wireless radio access point for relaying transmissionand which thus does not implement all of the functionalities of a basestation. It is in general not directly connected to the core network butuses wireless access (inband or outband) for backhaul link to connectwith a base station. In other examples, the backhaul link may also beprovided over a wired connection. This is in contrast to a small cellbase station which, as mentioned above, can generally operate like abase station and is thus connected to the core network, as illustratedby the arrows between the small cell base stations 211-216 and theServing Gateway “S-GW” in FIG. 2.

As previously mentioned, it is envisaged that V2X communications willmake use of device-to-device (D2D) communication techniques. However, aspreviously mentioned, because different vehicles travel at differentspeeds, there are certain characteristics of the D2D communicationtechniques used which may be adjusted depending on the speed of avehicle so as to help allow reliable communication between vehicles. Inparticular, the communication resources (in particular, radio resources,such as LTE resource blocks) used for D2D communication may be made todepend on the speed of a vehicle. It is the implementation of such aspeed dependence on the communication resources used for D2Dcommunication which is addressed by the present technique.

In an embodiment of the present technique, communication resources areprovided to the V2X UE. The communication resources are selecteddependent on the speed of the vehicle on or within which the V2X UE islocated. The coverage area of the communication resources used may bedifferent depending on the speed (for example, low mobility resourcesfor lower speed vehicles may be cell specific, where as high mobilityresources for higher speed vehicles may be specific to a larger numberof cells in order to avoid frequent reconfiguration during atransmission). Properties of the resource sets may also differ. Forexample, the resource sets may be configured in a particular way so asto support UEs at particular speeds. Furthermore, the mode of operationmay differ. For example, slower speed UEs may use a scheduled resourceallocation mode (either communicating with other UEs via an eNB or RSU,or being scheduled to perform D2D communication with other UEs by aneNB). Those UEs may then switch to using D2D autonomous resourceallocation at higher speeds (autonomous resource allocation requiring nosignalling from an eNB or RSU in order for resources to be allocated tothe UE) so that frequent cell change or potential connection or handoverfailure does not impact the ongoing direct communication betweenvehicles. Alternatively, the reverse may be configured, to give tighternetwork control at higher speeds. The configuration signalling ofresources may also differ. For example, depending on the spanned area ofthe resources and the operation mode, the notification signalling whichallows communication resources to be allocated for use by V2X UEs (suchas broadcast signalling, dedicated signalling or inter-eNB (inter-PLMN(Public Land Mobile Network)) coordination) may be different.

In a further embodiment of the present technique, the determination ofthe speed of a V2X UE by that UE may be enhanced by utilising externalequipment to the UE. For example the built in speedometer of a vehicleprovides a more accurate speed and acceleration estimation thanconventional 3GPP methods (which are based on, for example, counting thenumber of cell changes in order to estimate the UE speed), and thus theUE may determine its speed based on an input to the UE from the vehiclespeedometer. Alternatively, the UE may determine its speed based on aninput to the UE from a satellite navigation device (such as a GlobalPositioning System (GPS) device). Taking advantage of such methods ofspeed estimation allows for more precise tuning of parameters (includingthe communication resources to be used) than current 3GPP mobility stateestimation techniques. In particular, the more accurate mobilityestimation may be reported to an eNB, allowing the eNB to performresource configuration based on the report, or a UE may automaticallytake it into account based on a plurality of configurations or based onscaling of parameters.

In a further embodiment of the present technique, other input data maybe used to help select appropriate communication resources. For example,an image sensor can be used to detect collisions early and an input fromthe image sensor may then be used to switch resource set used by the UE.

Further details about embodiments of the present technique are describedin more detail below.

FIG. 3 schematically illustrates infrastructure equipment 201 accordingto an embodiment of the present disclosure. The infrastructure equipment201 may be, for example, a base station or an RSU. The infrastructureequipment 201 comprises a transmitter 402 for transmitting data to aterminal device (or UE), a receiver 404 for receiving data from aterminal device and a storage medium 406 for storing informationidentifying communication resources for use by a terminal device inperforming D2D communication with another terminal device. The operationof each of the transmitter 402, receiver 404 and storage medium 406 iscontrolled by the controller 400. It is also noted that the transmitter402 and receiver 404 together form a transceiver. In the followingdescription, the infrastructure equipment is a base station. However, itwill be appreciated that the following description will also apply ifthe infrastructure equipment is an RSU.

FIG. 4 schematically illustrates a terminal device 500 according to anembodiment of the present disclosure. The terminal device comprises atransmitter 504 for transmitting data to infrastructure equipment or toanother terminal device (using a D2D communication technique, forexample), a receiver 506 for receiving data from infrastructureequipment or from another terminal device (again, using a D2Dcommunication technique, for example) and a storage medium 508 forstoring information identifying communication resources for use by theterminal device in performing D2D communication with another terminaldevice. The speed of the terminal device 500 may be determined by thecontroller 502 based on known 3GPP mobility estimation techniques.Alternatively, the terminal device may comprise an interface 510 (asshown as an optional component of the terminal device 500) for enablingcommunication of the terminal device 500 with another, external device(such as a vehicle speedometer or satellite navigation device, forexample) configured to determine the speed of the terminal device 500and input the speed to the controller 502 of the terminal device 500 viathe interface 510. The operation of each of the transmitter 504,receiver 506, storage medium 508 and interface 510 (where present) iscontrolled by the controller 502. It is noted that the transmitter 504and receiver 506 together from a transceiver. Each V2X UE according toembodiments of the present technique has a structure as shown in FIG. 4.

FIG. 5 schematically shows one embodiment of the present technique. Inthis embodiment, the network (NW) configures multiple communicationresource pools for D2D autonomous resource selection by a UE, and the UEselects one of the resource pools depending on its mobility state. It iscurrently known that multiple resource pools can be configured for D2D,and thus, with this embodiment, an associated mobility state is added toeach resource pool (so that a first resource pool is associated with afirst mobility state, a second resource pool is associated with a secondmobility state, and so on). It is noted that a mobility state representsthe speed of the UE relative to infrastructure equipment of the network(such as base stations, RSUs and the like). The possible mobility statesmay be, for example, low (representing a first range of possible speedsof the UE), medium (representing a second range of possible speeds ofthe UE, each possible speed in the second range being higher than eachpossible speed in the first range) and high (representing a third rangeof possible speeds of the UE, each possible speed in the third rangebeing higher than each possible speed in the second range). Aspreviously mentioned, it is currently known to estimate the mobilitystate of a UE based on counting the number of cell changes within agiven time (this is carried out by the controller 502 of the UE). Thisestimation technique could be re-used in determining the appropriateresource pool. Alternatively, however, the UE may utilise the moreaccurate speed estimation methods already available, such as thespeedometer which is already built in to a vehicle, by use of satellitenavigation (sat nav) estimation, by using sensors placed externally onthe vehicle such as image sensors to estimate relative speed compared toanother vehicle, or by using any other suitable instruments which may beavailable in the vehicle. In general, it will be appreciated that anyexternal equipment suitable for determining the speed of the UE as ittravels may be used by the UE for speed estimation. As previouslydescribed, the input from such external equipment is input to thecontroller 502 of the UE for mobility state estimation via the interface510.

An example implementation of the first embodiment is shown in FIG. 5.Here, signalling between a base station 201 and two UEs 500A and 500B(each of these being a V2X UE) is shown. At a first step 601, the basestation notifies UE 500A of the resource pools associated with eachmobility state. Each resource pool is a set of predeterminedcommunication resources (such as LTE resource blocks) which have beenselected by the network for use by the UE 500A in performing D2Dcommunication with other UEs (such as UE 500B) at a particular mobilitystate of the UE 500A. In this example, the resource pools (together withthe mobility state associated with each resource pool) are notified tothe UE 500A via LTE System Information Blocks (SIBs), although it willappreciated that any other suitable technique of signalling the resourcepools and associated mobility states to the UE 500A could be used. Itwill also be appreciated that the UE 500A may be preconfigured withinformation identifying the resource pools (for example, duringmanufacture or via a software update), in which case the initialsignalling from the network during step 601 would not be required.

Once the resource pools and associated mobility states have beenreceived by the UE 500A, at a second step 603, the UE 500A determinesits speed (using one of the techniques previously described). At step603, the UE 500A determines its speed to be 30 miles per hour (mph). 30mph falls within the mobility state associated with resource pool A(thus, resource pool A is associated with a mobile state defined by arange of possible speeds which includes 30 mph), and thus, in step 605,the UE 500A proceeds to perform D2D communication with the UE 500B usingcommunication resources from the resource pool A.

At a later time, however, at step 607, the UE 500A once again determinesits speed and determines that it is now travelling at 60 mph. This mayhappen, for example, if the vehicle within which the UE 500A is locatedleaves a slower road in which the speed limit is 30 mph and joins afaster road in which the speed limit is 60 mph. 60 mph falls within themobility state associated with resource pool B (thus, resource pool B isassociated with a mobile state defined by a higher range of possiblespeeds which includes 60 mph), and thus, in step 607, the UE 500Aswitches to perform D2D communication with the UE 500B usingcommunication resources from the resource pool B.

It is noted that, in an embodiment, the communication resources includedin each resource pool are determined based on a characteristic of thosecommunication resources that make them suitable for the mobility stateassociated with that pool. For example, the communication resourcesallocated to resource pool B may be associated with a wider coveragearea (for example, they may allocated to the UE 500A for use in D2Dcommunication by other neighbouring base stations of the base station201) than the communications resources allocated to pool A. This allowshandover to the use of different communication resources for D2Dcommunication to be required less often when the UE 500A is travellingat higher speeds, thus reducing the chance of delay or failure. To putthis in more detail, if the coverage area associated with resource poolsA and B were the same, then handover to different resource pools (forexample, as the UE 500A leaves the coverage area of base station 201 andenters the coverage area of a different base station which allocatesdifferent resources for D2D communication) would occur more often forhigh speed UEs (which will leave the coverage area of any given basestation more quickly) than for low speed UEs (which will leave thecoverage area of any given base station more slowly). This isundesirable, since such handover is associated with a risk of delay orfailure, and such delay or failure increases the risk that there may bea time period in which high speed UEs suddenly cannot communicate witheach other. By providing a wider coverage resource pool B (for higherspeeds) and a lower coverage resource pool A (for lower speeds), thisproblem is therefore alleviated.

It is also envisaged that each resource pool may have differences inanother characteristic (instead of or in addition to coverage area) soas to improve their suitability for the mobility state with which theyare associated. For example, the resources could be selected based ontransmission format or the like (for example, with the transmissionformat of the communication resources of pool A being chosen for thelower mobility state associated with pool A and the transmission formatof the communication resources of pool B being chosen for the highermobility state associated with pool B). It will be appreciated the D2Dcommunication resources allocated for use by UEs in different mobilitystates could differ in any number of characteristics so as to improvetheir suitability for a particular mobility state.

FIG. 6 schematically shows another embodiment of the present technique.In this case, instead of resource pools for each mobility state beingdetermined by the network and notified to a UE in advance (for the UE tothen autonomously choose which resource pool to use depending on itsspeed, as is the case in the arrangement FIG. 5), the base station 201instead schedules appropriate communication resources to the UE based onreports received from the UE which indicate the speed of the UE. Inparticular, the UE requesting resources from the network may include aspeed estimation indication in, for example, the D-SR (DedicatedScheduling Request) or BSR (buffer status report) or a new MAC ControlElement (MAC CE), or the UE could separately update the network of itsspeed using radio resource control (RRC) signalling whenever the speedchanges. This would enable the eNB to determine which resources would bebest suited (based on characteristics such as coverage area,transmission format, etc., as previously discussed), and allocateresources to the UE accordingly.

An example implementation of such an embodiment is shown in FIG. 6. Atstep 701, an RRC connection is established between the base station 201and UE 500A. At step 702, the UE 500A then determines its current speed.In the example of FIG. 6, the UE's speed is 30 mph. At step 703, the UE500A transmits a D2D scheduling request to the base station 201. The D2Dscheduling request includes the current speed of the UE (30 mph). Atstep 704, the network, based on the speed reported by the UE, determinescommunication resources for use by the UE in performing D2Dcommunication. These resources are then allocated and scheduled to theUE 500A at step 705. At step 706, the UE 500A then performs D2Dcommunication with the UE 500B using the resources scheduled during step705.

Whenever the UE 500A detects a change in its speed (or, alternatively,for example, a change in speed which exceeds a predetermined changethreshold), steps 703 to 706 can be repeated so that, if there are moresuitable communication resources for use by the UE 500A at this newspeed, then these new resources can be scheduled to the UE 500A by thenetwork. This allows the most appropriate communication resources to beallocated to the UE 500A at a given speed. It will also be appreciatedthat other communication configurations (such as transmission format orthe like, as previously discussed) could also be notified to the UE in asimilar way.

FIG. 7 schematically shows another embodiment of the present technique.In this embodiment, when the UE 500A determines that it is travellingbelow a predetermined threshold speed, the UE 500A performs D2Dcommunication with the UE 500B using communication resources of aresource pool which has been notified to the UE in advance (in the sameway as discussed with reference to FIG. 5). On the other hand, when theUE 500A determines that it is travelling above the predeterminedthreshold speed, then it transmits a scheduling request to the basestation 201. In response, the base station 201 then schedules specificD2D resources for use by the UE 500A in exchanging signalling with UE500B (in the same way as discussed with reference to FIG. 6). Thus, atlower speeds (that is, speeds below the predetermined threshold speed),the UE 500A selects D2D communication resources autonomously without theneed for additional signalling from the network. On the other hand, athigher speeds (that is, speeds above the predetermined threshold speed),the UE 500A uses D2D resources which have been scheduled to it by thenetwork, thus allowing tighter coordinated resource scheduling forhigher speed vehicles (which may travel past several base stations orRSUs in quick succession) and reducing the chance of high speed vehiclecollision.

An example implementation of such an embodiment is shown in FIG. 7. Atstep 801, the base station 201 notifies the UE 500A of the resource poolconfiguration (including the communication resources allocated to eachpool, the mobility state with which each pool is associated, thetransmission format associated with each pool, etc., as previouslydiscussed). At step 802, the UE 500A determines its current speed. Inthe example of FIG. 7, the speed of the UE 500A is determined to be 30mph. This is below the predetermined threshold speed (which, in thisexample, is 60 mph), and therefore, at step 803, the UE 500A performsD2D communication with the UE 500B using communication resources fromthe resource pool associated with the mobility state associated with 30mph. The UE 500A will continue performing communication with the UE 500Bin this way (that is, using the predefined resource pools) for as longas its speed remains below the predetermined threshold.

At step 804, however, the UE 500A determines its speed to be 60 mph. Thepredetermined speed threshold of 60 mph is therefore met. In response,an RRC connection between the UE 500A and base station 201 is initiatedat step 805. The UE 500A then transmits a scheduling request to the basestation 201 at step 806. In response, the base station schedulesspecific D2D resources to the UE 500A at step 807. At step 808, the UE500A then performs D2D communication with the UE 500B using the newlyscheduled resources (rather than communication resources from one of thepredefined resource pools, as occurred previously).

It is noted that an alternative to the arrangement of FIG. 7 is that theUE uses the notified resource pools at lower speeds (as per FIG. 7), butthen instead of triggering RRC connection and then being configured withscheduled resource allocation once the predetermined threshold speed hasbeen reached, the base station 201 may instead provide a new resourcepool to the UE 500A to use in the autonomous mode at higher speeds. Theresources pools used at low speed will be applicable in that cell. Onthe other hand, when the network provides a new resource pool to the UE500A using dedicated signalling in the case that the predeterminedthreshold speed is exceeded, these resources could be valid even aftercell change (thus allowing use of these resources over a wider coveragearea and allowing the benefit of reduced risk of handover delay orfailure to be realised). The area validity for a new pool of resourcesmay be provided in the dedicated signalling from the base station 201 tothe UE 500A which configures the resources.

It will also be appreciated that the embodiment of FIG. 7 could beimplemented the other way round, that is, so that resources arescheduled to the UE 500A in response to the UE 500A transmitting ascheduling request at lower speeds, and then, once the predeterminedthreshold speed has been exceeded, the UE 500A starts using resourcesfrom a predefined resource pool allocated for use by the UE 500A athigher speeds. Thus, in this alternative embodiment, when the UE 500A istravelling below 60 mph, it will use resources scheduled to it by thebase station 201 (or, alternatively, lower speed resource poolsallocated to it by the base station 201), but once the UE 500A reaches60 mph (as the predetermined threshold speed), it will use the resourcesof a predefined high speed resource pool. One or more high speedresource pools may be notified to the UE 500A using the same techniqueas used in step 801 in FIG. 7 for allocating low speed resource pools(for example, using SIBs). Using this alternative embodiment, the needfor handover operations is reduced at higher speeds because the UE 500Aalready knows to use communication resources from a predefined resourcepool and does not have to wait for notification of which resources touse from a base station. The risk of communication failure due tohandover failure or delay is therefore reduced. In this case, thepredefined resource pools are common to a plurality of base stationsover a predetermined geographical area (for example, they are broadcastby each base station over a predetermined geographical area) and thusthe UE 500A may perform D2D communication with other UEs when travellingat high speed using communication resources from the predefined resourcepools when located at any point within the predetermined geographicalarea.

In another embodiment, communication resources (either forming part of aresource pool provided to a UE or being scheduled to a UE) may beassociated with a predetermined priority as well as with a predeterminedmobility state. The priorities may be associated with certain areas (forexample, certain busy roads) or certain vehicles (for example, emergencyvehicles such as the police, fire or ambulance). In this case,communication resources may be used by a UE when both speed and priorityrequirements are met. For example, there may be resources associatedwith high speed (for example, the highest mobility state) and highpriority. UEs could then only use those resources when they have thehighest mobility state and satisfy the appropriate high priorityrequirement. For example, the UE may have to be travelling on a certainroad (for example, this could be determined by a sat nav system, orcould be determined based on the base station or RSUs within range ofthe UE) or may have to be associated with a certain type of vehicle suchas an emergency vehicle (whether or not this is the case could bepre-programmed into the controller 502, for example). When both themobility state and priority requirements of particular resources are metby a UE, resources from a resource pool associated with that mobilitystate and priority may be selected (in the case of autonomous resourceselection mode) or resources associated with that mobility state andpriority may be indicated in the scheduling request (scheduled resourceselection mode). It will be appreciated that there are many ways inwhich different communication resources could be associated withdifferent factors (such as priorities) in addition to being associatedwith different UE mobility states.

In a further example, the resource selection is not only based on speed,but also on input from other instruments in the vehicle such as an imagesensor indicating that there is a chance of a collision. Such imagesensors are known. For example, in some vehicles, they are used todetect when there is a chance of a collision and input from the sensoris used to trigger automatic braking of the vehicle. In an embodiment,such sensors are used to trigger certain resources (in particular,certain resource pools) to be used in V2X communication. Certain commonand/or pre-configured communication resources which have been configuredin advance may be allocated for use during events with differentpriority levels (so that, for example, one set or resources is used inresponse to detection of a life critical event, a different set ofresources is used in response to a warning event, a different set ofresources is used in response to a periodical event, etc.). In oneexample, once a life critical event has been triggered (based on inputfrom the image sensor), the UE will select the resources allocated foruse during a life critical event from a resource pool. This isautonomous resource selection, and has the benefit of reduced delay.Alternatively, the UE may send a scheduling request to an RSU or basestation for the utilization of the resources allocated for use during alife critical event. This is scheduled resource selection, and has thebenefit of better coverage (since the network can co-ordinate all otherUEs in the area such that they can receive signalling using theallocated resources). In this latter case, every potential receiver UEwill periodically check the scheduling assignment information for theset of resources allocated to life critical events, and will switch tousing these resources in the case that a life critical event hasoccurred (as indicated by the scheduling assignment information). Thiswill allow each potential receiver UE to receive signalling from the UEwhich detected the life critical event using these resources. It isnoted that input from a crash detecting image sensor (as described) maybe provided to the controller 502 of a UE via the interface 510.

It is noted that the above-mentioned resource pool configuration mayalso be applied in respect of scheduling control (SC) resources. Forexample, separate pools of SC resources may be configured based onmobility state and/or other criteria such as event priority level. It ispossible for multiple SC pools to map to one data resource pool. Forexample, low and intermediate SC pools may point to the same shared dataresource pool.

Thus, embodiments of the present technique provide a first terminaldevice (such as terminal device 500A) for use with a wirelesstelecommunications system. The first terminal device comprises atransceiver (formed from a transmitter 504 and receiver 506) operable toexchange signalling with a second terminal device (such as terminaldevice 500B) using communication resources from one of a plurality ofsets of communication resources, each set of communication resourcesbeing associated with a different respective range of possible speeds ofthe first terminal device as determined in accordance with apredetermined characteristic (such as coverage area, transmissionformat, etc.) of the sets of communication resources. The first terminaldevice also comprises a controller 502 operable to control thetransceiver to exchange signalling with the second terminal device usingcommunication resources from the set of communication resourcesassociated with the range of possible speeds of the first terminaldevice within which a determined speed of the first terminal device isfound. It is noted that the second terminal device has the same internalstructure as the first terminal device (as shown in FIG. 4).

The transceiver of the first terminal device is operable to receivesignalling from infrastructure equipment (such as base station 201 or anRSU) identifying communication resources for use by the first terminaldevice in exchanging signalling with the second terminal device, thecommunication resources identified by the signalling received from theinfrastructure equipment being selected by the infrastructure equipmentfrom one or more of the sets of communication resources.

In one embodiment (as exemplified in FIG. 5, for example), thesignalling received from the infrastructure equipment identifies thecommunication resources of each of the sets of communication resources.In this case, each set of communication represents a resource pool whichis indicated to the first terminal device. The controller 502 thusdetermines the speed of the first terminal device (using input fromexternal equipment via the interface 510, for example), selects the setof communication resources associated with the range of possible speedsof the first terminal device within which the determined speed of thefirst terminal device is found (thus selecting the appropriate resourcepool), and controls the transceiver to exchange signalling with thesecond terminal device using communication resources from the selectedset. The information identifying each resource pool is stored in thestorage medium 508 of the first terminal device.

In another embodiment, the controller 502 of the first terminal devicedetermines the speed of the first terminal device. It then controls thetransceiver to transmit signalling to the infrastructure equipmentidentifying the determined speed, and to then receive signalling fromthe infrastructure equipment identifying communication resources for useby the first terminal device in exchanging signalling with the secondterminal device. The identified communication resources arecommunication resources from the set of communication resourcesassociated with the range of possible speeds of the first terminaldevice within which the determined speed of the first terminal device isfound. In this case, the identified communication resources may form aresource pool from which the controller may select communicationresources for use in exchanging signalling with the second terminaldevice. Alternatively, the identified communication resources may bescheduled to the first terminal device. The controller 502 then controlsthe transceiver to exchange signalling with the second terminal deviceusing a portion of the identified communication resources (for example,by selecting resources from the newly identified resource pool or byusing the scheduled resources). The information identifying theidentified communication resources is stored in the storage medium 508of the first terminal device.

In another embodiment, the signalling received from the infrastructureequipment identifies the communication resources of each of a portion ofthe sets of communication resources, each set in the portion of setsbeing associated with a different respective range of possible speeds ofthe first terminal device within a predetermined speed constraint. Theidentified communication resources of each set thus form respectiveresource pools, and the information identifying each resource pool isstored in the storage medium 508 of the first terminal device. Thecontroller 502 then determines the speed of the first terminal deviceand determines whether the speed of the first terminal device is withinthe predetermined speed constraint. If it is determined that the speedof the first terminal device is within the predetermined speedconstraint, then the controller 502 selects the set of communicationresources already identified in the signalling received from theinfrastructure equipment which is associated with the range of possiblespeeds of the first terminal device within which the determined speed ofthe first terminal device is found, and controls the transceiver toexchange signalling with the second terminal device using communicationresources from the selected set. On the other hand, if it is determinedthat the speed of the first terminal device is outside of thepredetermined speed constraint, then the controller 502 controls thetransceiver to transmit signalling to the infrastructure equipmentidentifying the speed of the first terminal device, and controls thetransceiver to receive new signalling from the infrastructure equipmentnewly identifying communication resources for use by the first terminaldevice in exchanging signalling with the second terminal device. Thenewly identified communication resources are communication resourcesfrom the set of communication resources associated with the range ofpossible speeds of the first terminal device within which the determinedspeed of the first terminal device is found. Again, the newly identifiedcommunication resources may form a resource pool from which thecontroller may select communication resources for use in exchangingsignalling with the second terminal device. Alternatively, the newlyidentified communication resources may be scheduled to the firstterminal device. The controller 502 then controls the transceiver toexchange signalling with the second terminal device using a portion ofthe newly identified communication resources (for example, by selectingresources from the newly identified resource pool or by using the newlyscheduled resources). The information identifying the newly identifiedcommunication resources is stored in the storage medium 508 of the firstterminal device.

In one embodiment, the predetermined speed constraint is that eachpossible speed of the first terminal device within the range of possiblespeeds associated with each set of communication resources in theportion of sets of communication resources is less than a predeterminedspeed. Alternatively, in another embodiment, the predetermined speedconstraint is that each possible speed of the first terminal devicewithin the range of possible speeds associated with each set ofcommunication resources in the portion of sets of communicationresources is greater than a predetermined speed. In the above examples,the predetermined speed is 60 mph (although it will be appreciated thatany other predetermined speed may be chosen depending on thecircumstances).

In one embodiment, the predetermined characteristic in accordance withwhich each set of communication resources is associated with a differentrespective range of possible speeds of the first terminal device is acell coverage area over which each set of communication resources isutilized. In particular, a set of communication resources utilised overa larger coverage area (by, for example, being common to severalinstances of infrastructure equipment over a predetermined geographicalarea) is associated with a higher range of possible speeds of the firstterminal device and a set of communication resources utilised over asmaller coverage area (by, for example, being associated only with oneinstance of infrastructure equipment over a predetermined geographicalarea) is associated with a lower range of possible speeds of the firstterminal device. It will also be appreciated that another predeterminedcharacteristic could be used for determining the different respectiverange of possible speeds with which each set of communication resourcesis associated, such as the transmission format used with thecommunication resources or the like.

In one embodiment, the controller 502 of the first terminal device isoperable to receive an input external equipment in order to determinethe speed of the first terminal device. This input is received viainterface 510. The external equipment may be, for example, a vehiclespeedometer, a sat nav system, or a vehicle image sensor whichdetermines the speed of a vehicle relative to another vehicle.

In one embodiment, the transceiver of the first terminal device isoperable to exchange signalling with the second terminal device usingcommunication resources from within one or more further sets ofcommunication resources, each further set of communication resourcesbeing associated with a different event priority level detectable by thefirst terminal device, the event priority level indicating a level ofseverity of an event detectable by the first terminal device. In otherwords, events with different levels of severity (that is, differentlevels of importance) are associated with different event prioritylevels. For example, there may be a further set of communicationresources allocated for use following detection of a life critical event(highest severity event priority level), a further set of communicationresources allocated for use following detection of a warning event(medium severity event priority level) and a further set ofcommunication resources allocated for use following detection of aperiodical event (lowest severity event priority level). The controller502 of the first terminal device is then operable to determine whetheran event has occurred (in response to, for example, input received froma vehicle image sensor via the interface 510), and when it is determinedthat an event has occurred, determine the event priority level of theevent (based on, for example, a predetermined relationship (such as alookup table) between detectable events and associated event prioritylevels stored in the storage medium 508), and control the transceiver toexchange signalling with the second terminal device using communicationresources from within the further set of communication resourcesassociated with the determined event priority level.

Embodiments of the present technique also provide infrastructureequipment (such as base station 201 or an RSU, an RSU, for the purposeof the present technique, having the same internal structure as basestation 201 as shown in FIG. 3) for use with a wirelesstelecommunications system. The infrastructure equipment comprises atransceiver (formed from transmitter 402 and receiver 404) and acontroller 400. The controller 400 is operable to control thetransceiver to transmit signalling to a first terminal deviceidentifying communication resources for use by the first terminal devicein exchanging signalling with a second terminal device. Thecommunication resources identified by the signalling transmitted by thetransceiver are selected by the controller from one or more of aplurality of sets of communication resources. Each set of communicationresources is associated with a different respective range of possiblespeeds of the first terminal device as determined in accordance with apredetermined characteristic of the sets of communication resources, andthe communication resources of a particular set of communicationresources are for use by the first terminal device in exchangingsignalling with the second terminal device when the first terminaldevice is travelling at a speed which is within the range of possiblespeeds associated with that particular set of communication resources.

In one embodiment, the signalling transmitted to the first terminaldevice identifies the communication resources of each of the sets ofcommunication resources. In this case, each set of communicationrepresents a resource pool which is indicated to the first terminaldevice. The information identifying each resource pool is stored in thestorage medium 406 of the infrastructure equipment.

In another embodiment, the transceiver of the infrastructure equipmentis operable to receive signalling from the first terminal deviceindicative of the speed of the first terminal device. The controller 400then determines communication resources for use by the first terminaldevice in exchanging signalling with the second terminal device, theidentified communication resources being communication resources fromthe set of communication resources associated with the range of possiblespeeds of the first terminal device within which the indicated speed ofthe first terminal device is found. In this case, the identifiedcommunication resources may form a resource pool from which the firstterminal device may select communication resources for use in exchangingsignalling with the second terminal device. Alternatively, theidentified communication resources may be scheduled to the firstterminal device. The transceiver then transmits signalling to the firstterminal device indicative of the determined communication resources.The information identifying the identified communication resources isstored in the storage medium 406 of the infrastructure equipment.

In another embodiment, the signalling transmitted to the first terminaldevice identifies the communication resources of each of a portion ofthe sets of communication resources, each set in the portion of setsbeing associated with a different respective range of possible speeds ofthe first terminal device within a predetermined speed constraint. Thereceived communication resources of each set thus from respectiveresource pools, and the information identifying each resource pool isstored in the storage medium 406 of the infrastructure equipment. Thetransceiver is furthermore operable to receive signalling from the firstterminal device indicative of the speed of the first terminal devicewhen the speed of the first terminal device is outside of thepredetermined speed constraint. In response to receiving the signallingfrom the first terminal device indicative of the speed of the firstterminal device, the controller 400 is operable to newly determinecommunication resources for use by the first terminal device inexchanging signalling with the second terminal device, the newlydetermined communication resources being communication resources fromthe set of communication resources associated with the range of possiblespeeds of the first terminal device within which the determined speed ofthe first terminal device is found. Again, the newly determinedcommunication resources may form a resource pool from which the firstterminal device may select communication resources for use in exchangingsignalling with the second terminal device. Alternatively, the newlydetermined communication resources may be scheduled to the firstterminal device. The transceiver then transmits signalling to the firstterminal device indicative of the newly determined communicationresources. The information identifying the newly determinedcommunication resources is stored in the storage medium 406 of theinfrastructure equipment.

In one embodiment, the predetermined speed constraint is that eachpossible speed of the first terminal device within the range of possiblespeeds associated with each set of communication resources in theportion of sets of communication resources is less than a predeterminedspeed. Alternatively, in another embodiment, the predetermined speedconstraint is that each possible speed of the first terminal devicewithin the range of possible speeds associated with each set ofcommunication resources in the portion of sets of communicationresources is greater than a predetermined speed. In the above examples,the predetermined speed is 60 mph (although it will be appreciated thatany other predetermined speed may be chosen depending on thecircumstances).

In one embodiment, the predetermined characteristic in accordance withwhich each set of communication resources is associated with a differentrespective range of possible speeds of the first terminal device is acell coverage area over which each set of communication resources isutilised, wherein a set of communication resources utilised over alarger coverage area (by, for example, being common to several instancesof infrastructure equipment over a predetermined geographical area) isassociated with a higher range of possible speeds of the first terminaldevice and a set of communication resources utilised over a smallercoverage area (by, for example, being associated only with one instanceof infrastructure equipment over a predetermined geographical area) isassociated with a lower range of possible speeds of the first terminaldevice. It will also be appreciated that another predeterminedcharacteristic could be used for determining the different respectiverange of possible speeds with which each set of communication resourcesis associated, such as the transmission format used with thecommunication resources or the like.

In one embodiment, the controller 400 of the infrastructure equipment isoperable to control the transceiver to transmit signalling to the firstterminal device identifying further communication resources for use bythe first terminal device in exchanging signalling with the secondterminal device. The further communication resources identified by thesignalling transmitted by the transceiver are selected by the controllerfrom within one or more further sets of communication resources, eachfurther set of communication resources being associated with a differentevent priority level detectable by the first terminal device, the eventpriority level indicating a level of severity of an event detectable bythe first terminal device. In other words, events with different levelsof severity (that is, different levels of importance) are associatedwith different event priority levels. For example, there may be afurther set of communication resources allocated for use followingdetection of a life critical event (highest severity event prioritylevel), a further set of communication resources allocated for usefollowing detection of a warning event (medium severity event prioritylevel) and a further set of communication resources allocated for usefollowing detection of a periodical event (lowest severity eventpriority level). The communication resources of a particular further setof communication resources are for use by the first terminal device inexchanging signalling with the second terminal device when the firstterminal device determines that an event has occurred and that the eventpriority level of the determined event is the event priority levelassociated with that particular further set of communication resources.

Various embodiments of the present technique are described withreference to the following numbered clauses:

1. A first terminal device for use with a wireless telecommunicationssystem, the first terminal device comprising:

-   -   a transceiver operable to exchange signalling with a second        terminal device using communication resources from within one of        a plurality of sets of communication resources, each set of        communication resources being associated with a different        respective range of possible speeds of the first terminal        device, the association being determined in accordance with a        predetermined characteristic of the sets of communication        resources; and    -   a controller operable to control the transceiver to exchange        signalling with the second terminal device using communication        resources from within the set of communication resources        associated with the range of possible speeds of the first        terminal device within which a determined speed of the first        terminal device is found.        2. A first terminal device according to clause 1, wherein:    -   the transceiver is operable to receive signalling from        infrastructure equipment identifying communication resources for        use by the first terminal device in exchanging signalling with        the second terminal device, the communication resources        identified by the signalling received from the infrastructure        equipment being selected by the infrastructure equipment from        one or more of the sets of communication resources.        3. A first terminal device according to clause 2, wherein the        signalling received from the infrastructure equipment identifies        the communication resources of each of the sets of communication        resources, and the controller is operable to:    -   determine the speed of the first terminal device;    -   select the set of communication resources associated with the        range of possible speeds of the first terminal device within        which the determined speed of the first terminal device is        found; and    -   control the transceiver to exchange signalling with the second        terminal device using communication resources from the selected        set.        4. A first terminal device according to clause 1, wherein the        controller is operable to:    -   determine the speed of the first terminal device;    -   control the transceiver to transmit signalling to the        infrastructure equipment identifying the determined speed;    -   receive the signalling from the infrastructure equipment        identifying communication resources for use by the first        terminal device in exchanging signalling with the second        terminal device, the identified communication resources being        communication resources from the set of communication resources        associated with the range of possible speeds of the first        terminal device within which the determined speed of the first        terminal device is found; and    -   control the transceiver to exchange signalling with the second        terminal device using a portion of the identified communication        resources.        5. A first terminal device according to clause 2, wherein the        signalling received from the infrastructure equipment identifies        the communication resources of each of a portion of the sets of        communication resources, each set in the portion of sets being        associated with a different respective range of possible speeds        of the first terminal device within a predetermined speed        constraint, and the controller is operable to:    -   determine the speed of the first terminal device;    -   determine whether the speed of the first terminal device is        within the predetermined speed constraint;    -   if it is determined that the speed of the first terminal device        is within the predetermined speed constraint, select the set of        communication resources identified in the signalling received        from the infrastructure equipment which is associated with the        range of possible speeds of the first terminal device within        which the determined speed of the first terminal device is        found, and control the transceiver to exchange signalling with        the second terminal device using communication resources from        the selected set; and    -   if it is determined that the speed of the first terminal device        is outside of the predetermined speed constraint, control the        transceiver to transmit signalling to the infrastructure        equipment identifying the speed of the first terminal device,        control the transceiver to receive new signalling from the        infrastructure equipment newly identifying communication        resources for use by the first terminal device in exchanging        signalling with the second terminal device, the newly identified        communication resources being communication resources from the        set of communication resources associated with the range of        possible speeds of the first terminal device within which the        determined speed of the first terminal device is found, and        control the transceiver to exchange signalling with the second        terminal device using a portion of the newly identified        communication resources.        6. A first terminal device according clause 5, wherein the        predetermined speed constraint is that each possible speed of        the first terminal device within the range of possible speeds        associated with each set of communication resources in the        portion of sets of communication resources is less than a        predetermined speed.        7. A first terminal device according clause 5, wherein the        predetermined speed constraint is that each possible speed of        the first terminal device within the range of possible speeds        associated with each set of communication resources in the        portion of sets of communication resources is greater than a        predetermined speed.        8. A first terminal device according to any preceding clause,        wherein the predetermined characteristic in accordance with        which each set of communication resources is associated with a        different respective range of possible speeds of the first        terminal device is a cell coverage area over which each set of        communication resources is utilised, wherein a set of        communication resources utilised over a larger coverage area is        associated with a higher range of possible speeds of the first        terminal device and a set of communication resources utilised        over a smaller coverage area is associated with a lower range of        possible speeds of the first terminal device.        9. A first terminal device according to any one of clauses 3 to        7, wherein the controller is operable to receive an input from        external equipment in order to determine the speed of the first        terminal device.        10. A first terminal device according to any preceding clause,        wherein:    -   the transceiver is operable to exchange signalling with the        second terminal device using communication resources from within        one or more further sets of communication resources, each        further set of communication resources being associated with a        different event priority level detectable by the first terminal        device, the event priority level indicating a level of severity        of an event detectable by the first terminal device; and    -   the controller is operable to:    -   determine whether an event has occurred; and    -   when it is determined that an event has occurred, determine the        event priority level of the event, and control the transceiver        to exchange signalling with the second terminal device using        communication resources from within the further set of        communication resources associated with the determined event        priority level.        11. Infrastructure equipment for use with a wireless        telecommunications system, the infrastructure equipment        comprising:    -   a transceiver; and    -   a controller; wherein    -   the controller is operable to control the transceiver to        transmit signalling to a first terminal device identifying        communication resources for use by the first terminal device in        exchanging signalling with a second terminal device, wherein the        communication resources identified by the signalling transmitted        by the transceiver are selected by the controller from within        one or more of a plurality of sets of communication resources,        each set of communication resources being associated with a        different respective range of possible speeds of the first        terminal device as determined in accordance with a predetermined        characteristic of the sets of communication resources, and        wherein the communication resources of a particular set of        communication resources are for use by the first terminal device        in exchanging signalling with the second terminal device when        the first terminal device is travelling at a speed which is        within the range of possible speeds associated with that        particular set of communication resources.        12. Infrastructure equipment according to clause 11, wherein the        signalling transmitted to the first terminal device identifies        the communication resources of each of the sets of communication        resources.        13. Infrastructure equipment according to clause 11, wherein:    -   the transceiver is operable to receive signalling from the first        terminal device indicative of the speed of the first terminal        device;    -   the controller is operable to determine communication resources        for use by the first terminal device in exchanging signalling        with the second terminal device, the identified communication        resources being communication resources from the set of        communication resources associated with the range of possible        speeds of the first terminal device within which the indicated        speed of the first terminal device is found; and    -   the transceiver is operable to transmit signalling to the first        terminal device indicative of the determined communication        resources.        14. Infrastructure equipment according to clause 11, wherein the        signalling transmitted to the first terminal devices identifies        the communication resources of each of a portion of the sets of        communication resources, each set in the portion of sets being        associated with a different respective range of possible speeds        of the first terminal device within a predetermined speed        constraint, and wherein:    -   the transceiver is operable to receive signalling from the first        terminal device indicative of the speed of the first terminal        device when the speed of the first terminal device is outside of        the predetermined speed constraint;    -   in response to receiving the signalling from the first terminal        device indicative of the speed of the first terminal device, the        controller is operable to newly determine communication        resources for use by the first terminal device in exchanging        signalling with the second terminal device, the newly determined        communication resources being communication resources from the        set of communication resources associated with the range of        possible speeds of the first terminal device within which the        determined speed of the first terminal device is found; and    -   the transceiver is operable to transmit signalling to the first        terminal device indicative of the newly determined communication        resources.        15. Infrastructure equipment according to clause 14, wherein the        predetermined speed constraint is that each possible speed of        the first terminal device within the range of possible speeds        associated with each set of communication resources in the        portion of sets of communication resources is less than a        predetermined speed.        16. Infrastructure equipment according to clause 14, wherein the        predetermined speed constraint is that each possible speed of        the first terminal device within the range of possible speeds        associated with each set of communication resources in the        portion of sets of communication resources is greater than a        predetermined speed.        17. Infrastructure equipment according to any one of clauses 11        to 16, wherein the predetermined characteristic in accordance        with which each set of communication resources is associated        with a different respective range of possible speeds of the        first terminal device is a cell coverage area over which each        set of communication resources is utilised, wherein a set of        communication resources utilised over a larger coverage area is        associated with a higher range of possible speeds of the first        terminal device and a set of communication resources utilised        over a smaller coverage area is associated with a lower range of        possible speeds of the first terminal device.        18. Infrastructure equipment according to any one of clauses 11        to 17, wherein the controller is operable to control the        transceiver to transmit signalling to the first terminal device        identifying further communication resources for use by the first        terminal device in exchanging signalling with the second        terminal device, wherein the further communication resources        identified by the signalling transmitted by the transceiver are        selected by the controller from within one or more further sets        of communication resources, each further set of communication        resources being associated with a different event priority level        detectable by the first terminal device, the event priority        level indicating a level of severity of an event detectable by        the first terminal device, and wherein the communication        resources of a particular further set of communication resources        are for use by the first terminal device in exchanging        signalling with the second terminal device when the first        terminal device determines that an event has occurred and that        the event priority level of the determined event is the event        priority level associated with that particular further set of        communication resources.        19. A wireless telecommunications system comprising a first        terminal device according to any one of clauses 1 to 10, a        second terminal device with which the first terminal device is        operable to exchange signalling, and infrastructure equipment        according to any one of clauses 11 to 18.        20. A method of operating a first terminal device for use with a        wireless telecommunications system, the method comprising:    -   controlling a transceiver of the first terminal device to        exchange signalling with a second terminal device using        communication resources from within one of a plurality of sets        of communication resources, each set of communication resources        being associated with a different respective range of possible        speeds of the first terminal device, the association being        determined in accordance with a predetermined characteristic of        the sets of communication resources; and    -   controlling the transceiver to exchange signalling with the        second terminal device using communication resources from within        the set of communication resources associated with the range of        possible speeds of the first terminal device within which a        determined speed of the first terminal device is found.        21. A method of operating infrastructure equipment for use with        a wireless telecommunications system, the method comprising        controlling a transceiver of the infrastructure equipment to        transmit signalling to a first terminal device identifying        communication resources for use by the first terminal device in        exchanging signalling with a second terminal device, wherein the        communication resources identified by the signalling transmitted        by the transceiver are selected from within one or more of a        plurality of sets of communication resources, each set of        communication resources being associated with a different        respective range of possible speeds of the first terminal device        as determined in accordance with a predetermined characteristic        of the sets of communication resources, and wherein the        communication resources of a particular set of communication        resources are for use by the first terminal device in exchanging        signalling with the second terminal device when the first        terminal device is travelling at a speed which is within the        range of possible speeds associated with that particular set of        communication resources.        22. A first terminal device for use with a wireless        telecommunications system, the first terminal device comprising:    -   transceiver circuitry operable to exchange signalling with a        second terminal device using communication resources from within        one of a plurality of sets of communication resources, each set        of communication resources being associated with a different        respective range of possible speeds of the first terminal        device, the association being determined in accordance with a        predetermined characteristic of the sets of communication        resources; and    -   controller circuitry operable to control the transceiver to        exchange signalling with the second terminal device using        communication resources from within the set of communication        resources associated with the range of possible speeds of the        first terminal device within which a determined speed of the        first terminal device is found.        23. Infrastructure equipment for use with a wireless        telecommunications system, the infrastructure equipment        comprising:    -   transceiver circuitry; and    -   controller circuitry; wherein    -   the controller circuitry is operable to control the transceiver        circuitry to transmit signalling to a first terminal device        identifying communication resources for use by the first        terminal device in exchanging signalling with a second terminal        device, wherein the communication resources identified by the        signalling transmitted by the transceiver circuitry are selected        by the controller circuitry from within one or more of a        plurality of sets of communication resources, each set of        communication resources being associated with a different        respective range of possible speeds of the first terminal device        as determined in accordance with a predetermined characteristic        of the sets of communication resources, and wherein the        communication resources of a particular set of communication        resources are for use by the first terminal device in exchanging        signalling with the second terminal device when the first        terminal device is travelling at a speed which is within the        range of possible speeds associated with that particular set of        communication resources.

Numerous modifications and variations of the present disclosure arepossible in light of the above teachings. It is therefore to beunderstood that within the scope of the appended claims, the disclosuremay be practiced otherwise than as specifically described herein.

In so far as embodiments of the disclosure have been described as beingimplemented, at least in part, by software-controlled data processingapparatus, it will be appreciated that a non-transitory machine-readablemedium carrying such software, such as an optical disk, a magnetic disk,semiconductor memory or the like, is also considered to represent anembodiment of the present disclosure.

It will be appreciated that the above description for clarity hasdescribed embodiments with reference to different functional units,circuitry and/or processors. However, it will be apparent that anysuitable distribution of functionality between different functionalunits, circuitry and/or processors may be used without detracting fromthe embodiments.

Described embodiments may be implemented in any suitable form includinghardware, software, firmware or any combination of these. Describedembodiments may optionally be implemented at least partly as computersoftware running on one or more data processors and/or digital signalprocessors. The elements and components of any embodiment may bephysically, functionally and logically implemented in any suitable way.Indeed the functionality may be implemented in a single unit, in aplurality of units or as part of other functional units. As such, thedisclosed embodiments may be implemented in a single unit or may bephysically and functionally distributed between different units,circuitry and/or processors.

Although the present disclosure has been described in connection withsome embodiments, it is not intended to be limited to the specific formset forth herein. Additionally, although a feature may appear to bedescribed in connection with particular embodiments, one skilled in theart would recognize that various features of the described embodimentsmay be combined in any manner suitable to implement the technique.

REFERENCES

-   [1] RP-151109 “New SI proposal: Feasibility Study on LTE-based V2X    Services” from LG Electronics, CATT, Vodafone and Huawei (3GPP TSG    RAN Meeting #68 Malmo, Sweden, Jun. 15-18, 2015).-   [2] LTE for UMTS: OFDMA and SC-FDMA Based Radio Access, Harris Holma    and Antti Toskala, Wiley 2009, ISBN 978-0-470-99401-6.

1. Infrastructure equipment for use with a wireless telecommunicationssystem, the infrastructure equipment comprising: a transceiver; andcircuitry configured to transmit signalling to a first terminal deviceidentifying communication resources for use by the first terminal devicein exchanging signalling with a second terminal device, wherein thecommunication resources identified by the signalling transmitted by thetransceiver are selected from within one or more of a plurality of setsof communication resources, each set of communication resources beingassociated with a different respective range of possible speeds of thefirst terminal device as determined in accordance with a predeterminedcharacteristic of the sets of communication resources, and wherein thecommunication resources of a particular set of communication resourcesare for use by the first terminal device in exchanging signalling withthe second terminal device when the first terminal device is travellingat a speed which is within the range of possible speeds associated withthat particular set of communication resources.
 2. The infrastructureequipment according to claim 1, wherein the signalling transmitted tothe first terminal device identifies the communication resources of eachof the sets of communication resources.
 3. The infrastructure equipmentaccording to claim 1, wherein the circuitry is further configured toreceive signalling from the first terminal device indicative of thespeed of the first terminal device, determine communication resourcesfor use by the first terminal device in exchanging signalling with thesecond terminal device, the identified communication resources beingcommunication resources from the set of communication resourcesassociated with the range of possible speeds of the first terminaldevice within which the indicated speed of the first terminal device isfound, and transmit signalling to the first terminal device indicativeof the determined communication resources.
 4. The infrastructureequipment according to claim 1, wherein the signalling transmitted tothe first terminal devices identifies the communication resources ofeach of a portion of the sets of communication resources, each set inthe portion of sets being associated with a different respective rangeof possible speeds of the first terminal device within a predeterminedspeed constraint, and wherein the circuitry is further configured to:receive signalling from the first terminal device indicative of thespeed of the first terminal device when the speed of the first terminaldevice is outside of the predetermined speed constraint, in response toreceiving the signalling from the first terminal device indicative ofthe speed of the first terminal device, newly determine communicationresources for use by the first terminal device in exchanging signallingwith the second terminal device, the newly determined communicationresources being communication resources from the set of communicationresources associated with the range of possible speeds of the firstterminal device within which the determined speed of the first terminaldevice is found, and transmit signalling to the first terminal deviceindicative of the newly determined communication resources.
 5. Theinfrastructure equipment according to claim 4, wherein the predeterminedspeed constraint is that each possible speed of the first terminaldevice within the range of possible speeds associated with each set ofcommunication resources in the portion of sets of communicationresources is less than a predetermined speed.
 6. The infrastructureequipment according to claim 4, wherein the predetermined speedconstraint is that each possible speed of the first terminal devicewithin the range of possible speeds associated with each set ofcommunication resources in the portion of sets of communicationresources is greater than a predetermined speed.
 7. The infrastructureequipment according to claim 1, wherein the predetermined characteristicin accordance with which each set of communication resources isassociated with a different respective range of possible speeds of thefirst terminal device is a cell coverage area over which each set ofcommunication resources is utilised, wherein a set of communicationresources utilised over a larger coverage area is associated with ahigher range of possible speeds of the first terminal device and a setof communication resources utilised over a smaller coverage area isassociated with a lower range of possible speeds of the first terminaldevice.
 8. The infrastructure equipment according to claim 1, whereinthe circuitry is further configured to transmit signalling to the firstterminal device identifying further communication resources for use bythe first terminal device in exchanging signalling with the secondterminal device, wherein the further communication resources identifiedby the signalling transmitted by the transceiver are selected fromwithin one or more further sets of communication resources, each furtherset of communication resources being associated with a different eventpriority level detectable by the first terminal device, the eventpriority level indicating a level of severity of an event detectable bythe first terminal device, and wherein the communication resources of aparticular further set of communication resources are for use by thefirst terminal device in exchanging signalling with the second terminaldevice when the first terminal device determines that an event hasoccurred and that the event priority level of the determined event isthe event priority level associated with that particular further set ofcommunication resources.
 9. A method of operating infrastructureequipment for use with a wireless telecommunications system, the methodcomprising: transmitting signalling to a first terminal deviceidentifying communication resources for use by the first terminal devicein exchanging signalling with a second terminal device, wherein thecommunication resources identified by the signalling transmitted by thetransceiver are selected from within one or more of a plurality of setsof communication resources, each set of communication resources beingassociated with a different respective range of possible speeds of thefirst terminal device as determined in accordance with a predeterminedcharacteristic of the sets of communication resources, and wherein thecommunication resources of a particular set of communication resourcesare for use by the first terminal device in exchanging signalling withthe second terminal device when the first terminal device is travellingat a speed which is within the range of possible speeds associated withthat particular set of communication resources.
 10. The method of claim9, wherein the signalling transmitted to the first terminal deviceidentifies the communication resources of each of the sets ofcommunication resources.
 11. The method of claim 9, further comprising:receiving signalling from the first terminal device indicative of thespeed of the first terminal device; determining communication resourcesfor use by the first terminal device in exchanging signalling with thesecond terminal device, the identified communication resources beingcommunication resources from the set of communication resourcesassociated with the range of possible speeds of the first terminaldevice within which the indicated speed of the first terminal device isfound; and transmitting signalling to the first terminal deviceindicative of the determined communication resources.
 12. The method ofclaim 9, wherein the signalling transmitted to the first terminaldevices identifies the communication resources of each of a portion ofthe sets of communication resources, each set in the portion of setsbeing associated with a different respective range of possible speeds ofthe first terminal device within a predetermined speed constraint, themethod further comprising: receiving signalling from the first terminaldevice indicative of the speed of the first terminal device when thespeed of the first terminal device is outside of the predetermined speedconstraint; in response to receiving the signalling from the firstterminal device indicative of the speed of the first terminal device,newly determining communication resources for use by the first terminaldevice in exchanging signalling with the second terminal device, thenewly determined communication resources being communication resourcesfrom the set of communication resources associated with the range ofpossible speeds of the first terminal device within which the determinedspeed of the first terminal device is found; and transmitting signallingto the first terminal device indicative of the newly determinedcommunication resources.
 13. The method of claim 12, wherein thepredetermined speed constraint is that each possible speed of the firstterminal device within the range of possible speeds associated with eachset of communication resources in the portion of sets of communicationresources is less than a predetermined speed.
 14. The method of claim12, wherein the predetermined speed constraint is that each possiblespeed of the first terminal device within the range of possible speedsassociated with each set of communication resources in the portion ofsets of communication resources is greater than a predetermined speed.15. The method of claim 9, wherein the predetermined characteristic inaccordance with which each set of communication resources is associatedwith a different respective range of possible speeds of the firstterminal device is a cell coverage area over which each set ofcommunication resources is utilised, wherein a set of communicationresources utilised over a larger coverage area is associated with ahigher range of possible speeds of the first terminal device and a setof communication resources utilised over a smaller coverage area isassociated with a lower range of possible speeds of the first terminaldevice.
 16. The method of claim 9, further comprising: transmittingsignalling to the first terminal device identifying furthercommunication resources for use by the first terminal device inexchanging signalling with the second terminal device, wherein thefurther communication resources identified by the signalling transmittedby the transceiver are selected from within one or more further sets ofcommunication resources, each further set of communication resourcesbeing associated with a different event priority level detectable by thefirst terminal device, the event priority level indicating a level ofseverity of an event detectable by the first terminal device, andwherein the communication resources of a particular further set ofcommunication resources are for use by the first terminal device inexchanging signalling with the second terminal device when the firstterminal device determines that an event has occurred and that the eventpriority level of the determined event is the event priority levelassociated with that particular further set of communication resources.17. Infrastructure equipment for use with a wireless telecommunicationssystem, the infrastructure equipment comprising: transceiver circuitry;and controller circuitry, wherein the controller circuitry is configuredto control the transceiver circuitry to transmit signalling to a firstterminal device identifying communication resources for use by the firstterminal device in exchanging signalling with a second terminal device,wherein the communication resources identified by the signallingtransmitted by the transceiver circuitry are selected by the controllercircuitry from within one or more of a plurality of sets ofcommunication resources, each set of communication resources beingassociated with a different respective range of possible speeds of thefirst terminal device as determined in accordance with a predeterminedcharacteristic of the sets of communication resources, and wherein thecommunication resources of a particular set of communication resourcesare for use by the first terminal device in exchanging signalling withthe second terminal device when the first terminal device is travellingat a speed which is within the range of possible speeds associated withthat particular set of communication resources.